我正在尝试将 kivy 弹出窗口中的按钮绑定到 popup.dismiss 函数并不断收到错误

Question

我正在尝试将该popup.dismiss()功能绑定到BoxLayoutKivy 弹出窗口中a 内的按钮。

我不断收到错误消息：

None Type' 对象没有属性 'bind'。

我一直在寻找答案 2 天，但似乎无法找到我要找的东西。任何帮助，将不胜感激。

另外，如果您对我的代码有任何提示，我将不胜感激，因为我是新手，而且我确信其中有很多错误。

我没有添加 .kv 代码，因为我认为它不适用于我目前遇到的问题。

代码片段：

import kivy
kivy.require('1.9.1')

from kivy.app import App
from kivy.uix.tabbedpanel import TabbedPanel
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.gridlayout import GridLayout
from KivyCalendar import CalendarWidget
from KivyCalendar import DatePicker
from kivy.properties import ObjectProperty, OptionProperty
from kivy.uix.listview import ListItemButton
from kivy.uix.modalview import ModalView
from kivy.uix.popup import Popup
from kivy.uix.widget import Widget
from kivy.uix.label import Label
from kivy.uix.button import Button
from kivy.uix.textinput import TextInput

import sqlite3
import datetime


class LogSheet(TabbedPanel):

    def __init__(self, **kwargs):
        super(LogSheet, self).__init__(**kwargs)
        #self.register_event_type('popup_1')
        sq = sqlite3
        wd = Widget
        md = ModalView
        lb = Label
        op = OptionProperty
        bt = Button


    def popup_1(self):
            box = BoxLayout(orientation = 'vertical', padding = (10))
            box.add_widget(Label(text = "Are you sure you want to save data? \n Once saved cannot re-edit!!!!"))
            btn1 = box.add_widget(Button(text = "YES TO SAVE"))
            btn2 = box.add_widget(Button(text = "NO TO GO BACK"))

            btn1.bind(on_press = popup.dismiss)
            btn2.bind(on_press = hypochlorinator_1)

            popup = Popup(title='Check if Correct', title_size= (30), 
                          title_align = 'center', content = box,
                          size_hint=(None, None), size=(400, 400), auto_dismiss = True)
            popup.open() 

    def hypochlorinator_1(self):

        dd1 = self.date_data.text
        vd1 = self.volt_data.text
        ad1 = self.amp_data.text
        ld1 = self.load_data.text

        conn = sqlite3.connect('logsheet.db')
        c = conn.cursor()

        def create_table():
            c.execute('''CREATE TABLE IF NOT EXISTS logSheets(id INTEGER 
PRIMARY KEY,
            date DATETIME, volts REAL, amps REAL, setpoint REAL)''')


        def data_entry():

            c.execute('''INSERT INTO logSheets (date, volts, amps, setpoint) 
            VALUES (?, ?, ?, ?)''', (dd1, vd1, ad1, ld1))

            conn.commit()

        create_table()
        data_entry()
        c.close()
        conn.close()


class LogSheetApp(App):

    def build(self):
        return LogSheet()

lsApp = LogSheetApp()
lsApp.run()

错误信息：

File "C:\Users\Kids\Documents\Visual Studio 2015\Projects\KivyTuts2\logsheet.kv", line 294, in <module>
  on_press: root.popup_1()
File "C:\Users\Kids\Documents\Visual Studio 2015\Projects\KivyTuts2\logsheet.py", line 87, in popup_1
  btn1.bind(popup.dismiss)
AttributeError: 'NoneType' object has no attribute 'bind'

Answer 1

你有：

btn1 = box.add_widget(Button(text = "YES TO SAVE"))
btn2 = box.add_widget(Button(text = "NO TO GO BACK"))

btn1和btn2是add_widget方法的返回，也就是说，它们是None。您必须先实例化按钮，然后使用 add_widget 方法：

btn1 = Button(text = "YES TO SAVE")
btn2 = Button(text = "NO TO GO BACK")
box.add_widget(btn1)
box.add_widget(btn2)

现在，btn1和btn2是 Button 的实例，并且它们有bind方法。

您还可以将on_press参数传递给构造函数：

box.add_widget(Button(text = "YES TO SAVE",  on_press=popup.dismiss))
box.add_widget(Button(text = "NO TO GO BACK",  on_press=self.hypochlorinator_1))

你的功能应该是：

def popup_1(self):
    box = BoxLayout(orientation = 'vertical', padding = (10))
    box.add_widget(Label(text = "Are you sure you want to save data? \n Once saved cannot re-edit!!!!"))
    btn1 = Button(text = "YES TO SAVE")
    btn2 = Button(text = "NO TO GO BACK")
    box.add_widget(btn1)
    box.add_widget(btn2)

    popup = Popup(title='Check if Correct', title_size= (30), 
                  title_align = 'center', content = box,
                  size_hint=(None, None), size=(400, 400),
                  auto_dismiss = True)

    btn1.bind(on_press = popup.dismiss)
    btn2.bind(on_press = self.hypochlorinator_1)
    popup.open()

或者：

def popup_1(self):
    box = BoxLayout(orientation = 'vertical', padding = (10))
    box.add_widget(Label(text = "Are you sure you want to save data? \n Once saved cannot re-edit!!!!"))
    popup = Popup(title='Check if Correct', title_size= (30), 
                  title_align = 'center', content = box,
                  size_hint=(None, None), size=(400, 400),
                  auto_dismiss = True)
    box.add_widget(Button(text = "YES TO SAVE",  on_press=popup.dismiss))
    box.add_widget(Button(text = "NO TO GO BACK",  on_press=self.hypochlorinator_1))
    popup.open()

输出：

编辑： hypochlorinator_1应该收到一个额外的参数：

def hypochlorinator_1(self, instance):